Archive for the ‘Work File Only – Observer’s Challenge Reports’ category

NGC 3877 – Galaxy In Ursa Major: April 2020 Observer’s Challenge Report

February 28, 2020

MONTHLY OBSERVER’S CHALLENGE

Compiled by:

Roger Ivester, North Carolina

&

Sue French, New York 

April 2020

Report #135

NGC 3877 Galaxy in Ursa Major  

“Sharing Observations and Bringing Amateur Astronomers Together”

 

 

James R. Dire:  Observer from Illinois 

     NGC 3877 is an 11th magnitude spiral galaxy in the constellation Ursa Major. To find the galaxy start at the star Megrez, the star where the handle of the Big Dipper connects to the cup.  Follow an arcing line from Megrez through Phecda (bottom star in cup below Megrez) curving south to the third magnitude star El Kaphrah.  The three stars are close to equally spaced with El Kaphrah a tad dimmer than Megrez.  NGC 3877 is a mere 17 arc minutes directly south of El Kaphrah, making it one of the easiest 11th magnitude galaxies to find star hopping.

     NGC 3877 is a nearly edge on spiral galaxy 5.4 arc minutes long and 1.2 arc minutes wide. The galaxy is classified Sc, which means is has a very small core surrounded by whirling spiral arms. William Herschel discovered NGC 3877 in the year 1788 using his 18.7-inch Newtonian.

     Through an 8-inch telescope the galaxy looks cigar shaped with a bright stellar-looking core. No detail can be seen in the spiral arms. 

     I imaged NGC 3877 with an 8-inch f/8 Ritchey–Chrétien Cassegrain (with a Televue 0.8x focal reducer/field flattener yielding f/6.4) using an SBIG ST-2000XCM CCD camera.  The exposure was 180 minutes.

     To image this galaxy with a reflector is tricky because if you don’t get the star El Kaphrah out of the field, the required exposure to pick up the galaxy would cause the star to drown out the image.  In my image the bright star near the top of the image is 8th magnitude SAO43884.  El Kaphrah is outside of the field of view straight above (north) of the galaxy.  During my three-hour exposure, ghost reflections of El Kaphrah appeared on the image as well as two bright diffraction spikes from my secondary mirror spider.  I removed those from the final image.

     About 5 arc minutes to the northwest of the core (upper right) lies a magnitude 9.9 star with four diffraction spikes. Just below this star is a magnitude 16.7 star that is very red in color.  Just at the edge of the lower right diffraction spike is an even very fainted red star shining at magnitude 17.7.  This is one of the faintest stars in the image

     The image picks up the tightly wound spiral arms of the galaxy. In between the arms are several dark dust lanes.  The three stars that appear on the outskirts of the galaxy are Milky Way foreground stars.

fullsizeoutput_1244

 

Mario Motta:  Observer from Massachusetts

Taken last night (March 27-28) through 32-inch telescope.  Five min subs, total 60 minutes integration time. 

Camera is my new ZWO ASI6200.   Processed in PixInsight.   

NGC3877

 

Roger Ivester:  Observer from North Carolina 

Telescope:  10-inch f/4.5 reflector:  Date: February 22, 2020  

NGC 3877:  Dim slash with very low surface brightness, oriented NE-SW with a subtle brightening in the central region along the highly elongated core.  The galaxy arms show some mottling and uneven texture.  

Pencil sketch:  5 x 8 blank note card with the colors inverted:  

image001

 

Glenn Chaple:  Observer from Massachusetts 

The best star-hops are those that require no hopping at all. Such is the case with this month’s Observer’s Challenge, the near edge-on spiral galaxy NGC 3877. Center the magnitude 3.7 star Chi (χ) Ursae Majoris in the field of your scope’s finder and then peer into the eyepiece. If your eye is properly dark-adapted, you should see an oval haze just ¼ degree to the south.

In March of 1998, a supernova appeared in NGC 3877, quickly reaching 12th magnitude. It was visible in my 4-inch f/4 rich-field reflector (Edmund Scientific’s Astroscan), as was the galaxy itself. To see NGC 3877 with such a small aperture demands dark-sky conditions. In Vol. 2 of The Night Sky Observer’s Guide, authors George Kepple and Glen Sanner note that an 8 to 10-inch scope will reveal the galaxy’s central condensation, while scopes with twice the aperture should bring out the mottled appearance of its outer regions.

NGC 3877 was discovered by William Herschel on the night of February 5, 1788. Along with M109, it belongs to the Ursa Major Galaxy Cluster. Its distance is variously recorded as 42 to 50 million light years. If at the latter distance, NGC 3877 would span some 80,000 light-years.

Finder charts for NGC 3877 below. Bright star in right-hand chart (from AAVSO Variable Star Plotter) is Chi (χ) UMa. Numbers refer to magnitudes of field stars. North is up in this 25′ by 30′ field.

fullsizeoutput_1242

fullsizeoutput_1243

NGC 3877 and supernova 1998S, March 25, 1998. Magnification 74× FOV 20. North is to the right.  Sketch by Glenn Chaple (ATMoB)

 

Uwe Glahn:  Observer from Germany 

Objekt: NGC 3877

Teleskop: 27-inch  f/4.2 Newtonian 

Vergrößerung: 293x – 488x

Filter: /

Bedingungen: fst 6m5+

Seeing: III

Ort: Sudelfeld

Inverted Pencil Sketch: 

NGC3877_ug

 

Gus Johnson:  Observer from Maryland 

April 1998:  6-inch @ 118x with a first quarter moon.  Highly elongated with a bright core.  When observing with an 8-inch reflector @ 116x, the galaxy appears much brighter than the 6-inch, as to be expected.  However, mottling and unevenness could now be seen in the arms.  

 

 

 

 

NGC 2859 – Galaxy in Leo Minor: March 2020 Observer’s Challenge Report

February 27, 2020

MONTHLY OBSERVER’S CHALLENGE

Compiled by:

Roger Ivester, North Carolina

&

Sue French, New York

March 2020

Report #134

NGC 2859 Galaxy in Leo Minor

Sharing Observations and Bringing Amateur Astronomers Together

Introduction

The purpose of the Observer’s Challenge is to encourage the pursuit of visual observing. It’s open to everyone who’s interested, and if you’re able to contribute notes, and/or drawings, we’ll be happy to include them in our monthly summary. Visual astronomy depends on what’s seen through the eyepiece. Not only does it satisfy an innate curiosity, but it allows the visual observer to discover the beauty and the wonderment of the night sky. Before photography, all observations depended on what astronomers saw in the eyepiece, and how they recorded their observations. This was done through notes and drawings, and that’s the tradition we’re stressing in the Observer’s Challenge. And for folks with an interest in astrophotography, your digital images and notes are just as welcome. The hope is that you’ll read through these reports and become inspired to take more time at the eyepiece, study each object, and look for those subtle details that you might never have noticed before.

NGC 2859

NGC 2859 is a double-barred galaxy with an external ring that may be the remains of spiral arms that slowly detached themselves from the galaxy’s interior. Easier to observe, the central region is mostly spanned by a SSE to NNW bar with arcs capping each end, thus giving it a somewhat dumbbell-like appearance. NGC 2859 also hosts a small nuclear bar, nearly perpendicular to the first. The most current measurement places this galaxy at a distance of 93 ± 7 millon light-years.

William Herschel discovered NGC 2859 in 1786. His journal entry reads, “Very bright, much brighter in the middle, round, the brightness confined to a small place; the chevelure extending to about 3′ diameter.” 

Complete Observer’s Challenge Report Link as following:

March 2020 OBSERVERS CHALLENGE _ NGC 2859

 

Dale Holt: Observer from England, 30 miles north of London

IMG_1478

Dale introduces himself to challenge participants and readers:  

I use a 505mm f/3.74 Newtonian on a fork mount and an old analogue Watec 120N+ deep sky video camera with custom cooling. The camera is B&W and delivers its image in near real time, typically 15 sec exposure to a CRT monitor in my observatory office where I sketch from the screen. Most commonly I used graphite pencil on sketch paper although sometimes I use white on black hard pastels where the object is nebulous. Post drawing I scan the image and invert using paint. Limiting magnitude of my set up is around 19-20th mag.

I have given many talks over the past 15+ years in the UK on the amazing benefits of video astronomy, which is allowing successful observing in light polluted environments and also the relative increase in the punching power of your scope.

IMG_1473

 

 

 

 

 

 

 

 

Uwe Glahn:  Observer from Germany 

Telescope: 27-inch  f /4.2 Newtonian Reflector

Magnification: 172x and 293x

NELM 6.5 +

Seeing: IV

Location: Rossfeld

Pencil sketch as following:

IMG_1476

 

Michael Brown:  Observer from Massachusetts 

I photographed NGC 2859 on March 17, 2020.  The photo through my 8-inch SCT at f/6.3 had a total exposure of 16.5 minutes (33 images, each with 30-second exposure).  Given my modest astrophotography capabilities, the photo is imperfect and not spectacular.  Nevertheless, I am excited to have recorded an image of a galaxy that is over 80 million light-years distant and quite dim (magnitude 12.1 according to my Burnham’s Celestial Handbook).  Furthermore, several of the major features are visible, if only faintly in some cases.  This includes the bright core, the bar, the halo of stars that appears like a bubble around the bar and core, and finally, very faintly, the outer ring of stars (it’s definitely there!).  

On the night I took the images, I could see the galaxy visually, but did not spend much time on direct viewing.  I returned for more detailed visual observation on March 21.  

I found NGC 2859 easy to spot, forming a triangle with two stars in the same field, with the galaxy at a corner with an obtuse angle.  The galaxy appeared small with a stellar-like core.  There was clearly a hint of an extended halo or “nebulosity” surrounding the core.  I could not see the bar or the outer ring.

North is to the left, and west is up: 

NGC2859c Cropped

 

Sue French:  Observer From New York 

254/1494mm (10-inch f/5.8) Newtonian. Seeing: below average. Transparency: good. 

I logged this galaxy a couple times in the past, in 1983 and 2003. My only sketch of the galaxy was made for this Observer’s Challenge on 3-21-20.

At 43×, NGC 2859 was a faint, roundish glow near a yellow-orange, 7th-magnitude star. It was an easy star-hop 41 arcminutes E×N from orange Alpha (α) Lyncis.

A magnification of 115× showed a tiny, very bright nucleus; a small, bright core; and a faint halo.

The sketch was made from the view at 299×. To me, the core plus its bar looked somewhat like a spiral galaxy seen edge-on. This structure was enwrapped in a fainter halo spanning about 1½ arcminutes. There was no sign of the galaxy’s outer ring.

Alan and I took a look at C/2019 Y4 (ATLAS) after I was done. It was a large, pretty bright, diffuse glow — maybe a little brighter in the center.

IMG_1487

 

Mario Motta:  Observer from Massachusetts

A very interesting galaxy!   Imaged with my 32-inch, total 1 hour imaging time, SBIG 1001E camera.

This galaxy has a “ansae” type bar (which gets brighter at the tips of the bar) and an inner ring, no defined spiral structure, and a detached outer ring. 83 million light-years away, Leo Minor.

Fascinating object, you choose these objects very well, enjoy getting them.

NGC2859

 

James Dire:  Observer from Illinois 

NGC 2859 is a rare barred lenticular galaxy located on the southwest edge of the constellation Leo Minor.  The closest bright star is Alpha Lyncis.  The galaxy can be found 40 arcminutes east and 7 arcminutes north of this 3rd magnitude star.  The galaxy shines at magnitude 10.89 and is face-on measuring 4.6 x 4.1 arcminutes in size.

Barred lenticular galaxies like NGC 2859 are disk galaxies with no spiral arms.  The bars in these types of galaxies tend to be brighter at their edges. The bar in NGC 2859 is close to being due north-south as it is tilted only a few degrees to the west on the north side and east on the south side.  The galaxy also has a very faint detached ring beyond the disk containing the bar.  The galaxy’s core is quite bright compared to the rest of the galaxy.  The bar should be visible in 10 to 12-inch telescopes. The faint outer ring is beyond amateur telescopes visually and not counted in the quoted angular size of the galaxy.

I only managed to get one two-hour exposure of NGC 2859 this month due to an unusually cloudy winter here in Central Illinois.  The image was taken with an 8-inch f/8 Ritchey–Chrétien Cassegrain (with an 0.8x focal reducer/field flattener yielding f/6.4) with a SBIG ST-2000XCM CCD camera. I stretched the pixels containing the galaxy’s outer, detached ring, more than the rest of the image to make it more apparent. The bright star to the right of the galaxy is magnitude 7.2 SAO61446.  The other bright star, near the bottom of the image, is SAO61457 shining at magnitude 7.7.  

The yellow arrows show three very small faint galaxies captured in the same field of view as NGC 2859.  The one near the top is PGC26663, a magnitude 15.6 galaxy. To its right is magnitude 16.6 PGC3529815.  The third faint galaxy is PGC2048993, which is magnitude 17.6. This third galaxy appears to be an edge on spiral galaxy which appears brighter than the other two because its light is concentrated on a much smaller area.

NGC2859

 

Roger Ivester:  Observer from North Carolina 

Date: February 21, 2020

Telescope:  10-inch f/4.5 reflector

NELM:  4.9 

Very small, fairly bright, easy to locate and see at 57×.  When increasing the magnification to 208×, this galaxy is elongated, oriented NNW-SSE, however very subtle.  The core is much brighter than the outer round halo, which I could not see.

Pencil sketch:  5 × 8 blank note card with inverted colors.

image001

 

Mike McCabe:  Observer from Massachusetts

On Saturday evening, March 21st, 2020 I was able to view NGC 2859, a barred lenticular galaxy located 83 million light-years away in the constellation Leo Minor. The conditions on this evening were quite good for these parts, with the air temperature hovering around 30ºF, the transparency being at least 3/5, and the seeing around 2/5. I used a 10″ f/5 Newtonian telescope on a dob-style mount for this observation.

Finding the galaxy was a very straightforward process, as it fit into the 42× low power view with the naked-eye bright star Alpha Lyncis. The galaxy was clearly non-stellar at low power with a very bright core, but the nebulosity was not very evident.

Boosting up the magnification to 104× brought out a lot more nebulosity around the core, and that’s where I stopped to make my sketch. The galaxy itself was small and unremarkable, and I wasn’t able to get any sense of the orientation of it with regards to any elongation or direction of the bar.

Additionally, the star field took on an attractive aspect in the sense that it distinctly resembled an oversized version of Messier 29, the ‘cooling tower’ cluster in the constellation Cygnus.

IMG_1485

 

Joseph Rothchild:  Observer from Massachusetts

I observed galaxy NGC 2859 twice from dark skies in Cape Cod.  It was easy to locate with my 10-inch reflector near alpha Lynxis and 2 stars HD 80966 and HD 81057.  It was small faint, round, and with a stellar core.  There was no visible structure other than the core.

I observed it the same night as Comet Atlas C/2019 Y4.  NGC 2859 had a similar appearance to the comet, but the galaxy was fainter and much smaller.

 

Richard Nugent:  Observer from Massachusetts

NGC 2859 is a nearly 11th magnitude galaxy in Leo Minor. The galaxy is relatively easy to find. I moved  just 2/3 of a degree East of Alpha Lyncis to a pair of orange, 7th magnitude stars, HD80966 and HD81057.  

This galaxy lies just six arcminutes, a little south of East from HD80966.  NGC 2859 is fairly small, being 3 x 3 arcminutes and has a surface brightness of 14.0.  

I observed this month’s object from Framingham, MA (NELM is typically magnitude 4.8) using my 10 and 20-inch reflectors. Also, from the ATMoB site in Westford, MA (NELM overhead is around magnitude 5.1) using the club’s 25-inch telescope.  

The 10-inch scope showed the galaxy at medium and high magnifications.  At low power (50x) the galaxy was very difficult.  With the higher magnifications, it appeared as a small, round, diffuse glow that was brighter in the middle.  I couldn’t see any structure in the galaxy nor the outer ring, as seen in images.

The 20 and 25-inch scopes showed the galaxy better and of course, brighter but I still could not see any of the details visible in images.

All-in-all this is an easy galaxy to find and observe. While not particularly an impressive galaxy, you may still want to put on your yearly, March observing list.

 

Gary Shaw:  Observer from Massachusetts

Well my humble scope and I were both challenged by NGC 2859. We expected to see the galactic central as a blur – perhaps with highlights at opposing ends indicating the ansae brightening. But instead, we saw a stronger brightening at the ends than expected and saw no ‘bar’ to speak of. When I zoomed way in on the image, I could barely make out a faint bar shape crossing the “gaps” seen between the galactic center and the brightened NW and SE ends of the bar. 

Since capturing the attached image, I’ve had “first light” with a 200mm f/4 Newtonian and will give ole NGC 2859 another try. 

I’ve attached a wide field view and a little watercolor sketch which needs more work than the original observation did. I’m still in awe of everyone’s lovely pencil/charcoal sketches but I’m determined that by the end of 2020, I’ll have found a way to better capture the subtlety of these incredible objects in watercolor. 

I look forward to the April object. 

NGC 2859 Zoom

NGC 2859

 

John Bishop:  Observer from Massachusetts

Here is a summary of my efforts to see galaxy NGC 2859….

This month was a good news-bad news experience. The good news was that two clear nights would emerge for observing during the new moon period. The bad news was that, for entirely different reasons, I didn’t see NGC 2859 on either night.

On 3/21/20, I attempted to observe NGC 2859 from the ATMoB Clubhouse in Westford, MA.  The sky was clear; transparency and seeing were decent.  Instead of using my usual 8.25 inch reflector, but for a change of pace I decided to observe with my 5-inch f/8.1 apochromatic refractor.  It has a big heavy mount and tripod.  Perhaps you can guess why I don’t take it out much anymore.

Well, I got a reminder that aperture matters.  As hard as I tried, I could not see NGC 2859 through the 5-inch at any magnification…34x, 57x, 83x, and 138x. 

I understood the object to be somewhat stellar in appearance, but I could not tease out nebulosity around any of the objects in the field. The Apo’s optics are sharp, but that wasn’t enough. The reported surface brightness (Luginbuhl) is beyond the magnitude limit of the 5-inch.  However, the visual brightness is listed as mag. 10.7, so I thought I should be able to see it.  Frustrating!  

In consolation, I did see Comet PanSTARRS.  It was faint and nebulous. It looked like a classic Messier object. To locate the comet, I used a very interesting triple star, Iota Cassiopeia, as a reference point.  One of the components is much dimmer and  smaller than the others.  At least the Apo refractor had no trouble separating the trio.

Slightly mortified by my failure to locate NGC 2859, I made plans to go to the Clubhouse on 3/27/20 with my 8.25-inch reflector and find the object.  It was a clear, steady night.  Ideal, except more terrestrial concerns intervened. 

MIT, which owns the ATMoB Clubhouse, issued a directive prohibiting use of the Clubhouse and observing field until further notice, due to concerns over the coronavirus epidemic.  Especially frustrating, because at the moment I do not have another deep-sky observing site. 

This object may get away until next year.

 

Derek Lowe:  Observer from Massachusetts

We had a couple of clear nights, so I made sure to get out with the 18-inch Dob. The local police came by the field that I had set up in, and agreed with me that you can’t get much more socially distanced, and wished me a good evening.

So to galaxy, NGC 2859. 

I had logged this galaxy several years ago with my 11-inch Dob, and at the time noted that it was easily visible and appeared perfectly round like an unfocused star. I noted a concentrated core and coma, but no particular structure.  

This time around, I could see that the core took up some angular diameter of its own, and that the coma around it extended out further than was first apparent. This took a number of averted-vision passes – direct vision still gave just a fuzzball.  I certainly didn’t see any darkness separating the coma from the core, since the outermost part was quite faint.  What looked like the entire core in a quicker observation back with the 11-inch turned out out to be a brighter point in a round brightness of its own. 

Spending more time on the core itself, I could just barely make out the bar as a sort of brighter vertical streak the exact size of the “inner coma”.  This wasn’t easy to pick out, but every few tries it came into view.  A good example of an object that has a lot to see, once you know that it’s worth spending the time to dig them out!

 

 

NGC 1931 – Bright Nebula and Cluster in Auriga: February 2020 Observer’s Challenge Report

January 23, 2020

 

MONTHLY OBSERVER’S CHALLENGE

Compiled by:

Roger Ivester, North Carolina

&

Sue French, New York

February 2020

Report #133

NGC 1931 Bright Nebula and Cluster in Auriga 

Sharing Observations and Bringing Amateur Astronomers Together

Introduction

   The purpose of the Observer’s Challenge is to encourage the pursuit of visual observing. It’s open to everyone who’s interested, and if you’re able to contribute notes, and/or drawings, we’ll be happy to include them in our monthly summary. Visual astronomy depends on what’s seen through the eyepiece. Not only does it satisfy an innate curiosity, but it allows the visual observer to discover the beauty and the wonderment of the night sky. Before photography, all observations depended on what astronomers saw in the eyepiece, and how they recorded their observations. This was done through notes and drawings, and that’s the tradition we’re stressing in the Observer’s Challenge. And for folks with an interest in astrophotography, your digital images and notes are just as welcome. The hope is that you’ll read through these reports and become inspired to take more time at the eyepiece, study each object, and look for those subtle details that you might never have noticed before.

NGC 1931 

NGC 1931 is a small emission and reflection nebula with an involved cluster. The brightest part of the nebula has a trapezium system at its heart. Somewhat at odds with their name, trapezium systems can consist of more than four stars, and they don’t have to be arrayed in a trapezoidal shape. The term was initially coined to mean “a multiple star system whose pairwise separations are of the same order.” Some later researchers include groups whose stars may not be gravitationally bound. NGC 1931 is roughly 7500 light-years away from us.

William Herschel discovered this NGC 1931 in 1793. His journal entry reads, “Very bright, irregularly round, about 4 or 5′ diameter. Seems to have one or two stars in the middle or an irregular nucleus. The chevelure diminishes very gradually

 

February Observer’s Challenge Final:  Click on the Following link: 

February 2020 OBSERVERS CHALLENGE _ NGC 1931

February:  NGC 1931 – Bright  Nebula and Cluster – Auriga; Mag. V= 10.1;  Size 6′ 

RA:  05h  31m   Dec.  +34º  14′ 

 

The embedded Stars in NGC 1931:  by Sue French   

     Don’t be surprised about not seeing the stars in NGC 1931.  Folks get very mixed results.  Go to http://www.deepsky-archive.com/ and type NGC 1931 in the Designation box, then look at everyone’s sketches.  

     Here’s a long-ago Amastro post from Brian Skiff that gives the magnitudes of the trapezium system embedded in the brightest part of the nebula.  I see one of these stars, or a blend of them, in the 105mm scope.  The 10-inch at 213× gives me six stars in the brightest part of the nebulosity plus several mag 11-13½ stars scattered to the south.  I’ve pasted an image below Brian’s data and labeled the stars on it.  The image is in infrared so that the nebulosity doesn’t blot out the stars. Below the Aladin image is a WEBDA chart showing which stars I saw in the main group through the 10-inch..

     While cleaning up some star-lists, I collected data for stars in the nebulous open cluster NGC 1931 in Auriga.  The group contains a faint trapezium system, ADS 4112, that might be of interest to ‘amastro’ folks. The specs for the group are shown below.  The V magnitudes for the stars come from modern photoelectric or CCD studies.  The separations derive from positions in the 2MASS catalogue, which should be better than the 100-year-old visual micrometry, but which in any case match the old data to within a few tenths of an arcsecond. The brighter trio is straightforward in a small telescope; in 1989 I was able to make out the fourth ‘E’ component very faintly in my 6-inch refractor at 200x.  The very faint, close ‘D’ companion to star ‘B’ doubtless requires a very large aperture.  The data quoted for it is from S. W. Burnham’s work; the magnitude is possibly too bright.  The 2MASS coordinates are listed at the bottom.  Star ‘D’ does not appear in any astrometric catalogue.  The spectral types for the three brightest stars, by the way, are B0V, B0.5V, and B1V.  Thus the object should contain some emission, although there must be a substantial reflection component, since filters do not provide much contrast enhancement.   

\Brian

 ————————————————

ADS 4112 = BD+34 1074:  5 31 27  +34 14.9 (2000)

V mags      sep    pa

AB  11.5,12.3    8″.1  239

AC       13.0   10″.5  310

AE       14.0   14″.6   17

BD      (15.8)   2″.3  322

   

RA   (2000)   Dec

A   5 31 27.08  +34 14 49.6

B   5 31 26.54  +34 14 45.0

C   5 31 26.43  +34 14 56.3

E   5 31 27.50  +34 15 03.2

 

Sue French: Observer from New York

254/1494mm (10-inch f/5.8) Newtonian. Seeing: fair. Transparency: a little better than average.

43×: NGC 1931 is just a short hop westward from starfish-like M36. It presents a small hazy spot surrounding a star.

115×: The nebula spans about 3 arcminutes, and the star now appears triple. Several additional stars straggle south through west-southwest of the nebulous mass.

213×: Six stars are now buried in the nebulosity, three brightest members arranged in a little triangle.

The WEBDA cluster plot below marks the four trapezium-system stars viewed as well as two additional stars spotted within the nebula.

V-magnitudes of the trapezium stars according to WEBDA:

A=11.4, B=12.3, C=13.0, E=14.0. There is a component D in the trapezium system very close to B, but it’s thought to be magnitude 15.8 or dimmer and was not seen. The two arrowed stars were visible: the northern one shining at magnitude 14.1, and the southern one at magnitude 14.5.

After the star-plot is the sketch I made at 213× with the 10-inch scope on 17 February 2020 at 7pm EST. It was a pleasant night for February. The temperature was in the lower 20s and there was no wind. Unfortunately the seeing and transparency were both below average, and there was full snow cover on the ground. I couldn’t see the 14.5-magnitude star mentioned in the previous observation. I decided to sketch just the part of the nebula I could see and the four stars visible within it. My sketch looked pretty good to me, but a scanned image didn’t show the faintest parts, so I penciled over the original sketch to make it scan better, I hope without changing anything too much.

fullsizeoutput_1236Pencil Sketch:  Sue French:

North is up and west to the right

image002

 

 

Mario Motta: Observer from Massachusetts

Taken with my 32-inch telescope, and SBIG STL 1001E camera.  One hour of H-alpha, one hour of Sulfur S2 filters, and only 20 minutes of O3 filter as there was essentially no Oxygen signal.

Processed in PixInsight.

NGC1931

 

Roger Ivester: Observer from North Carolina 

On the night of January 28, 2020, the transparency and seeing were very good.  Using my 10-inch, f/4.5 reflector, NGC 1931 was very easy to locate and see at 57×, appearing as a star with a mostly round halo of nebulosity. 

When increasing the magnification to 267×, using a 12mm eyepiece and a 2.8× Barlow, the bright nucleus revealed a tiny trio of faint stars, with a fourth, much fainter star, toward the WSW.  This fourth star was extremely difficult, and could not be held constantly, but intermittently at best.  The nebula was elongated, with a NE-SW orientation.  

The first time I observed NGC 1931 was with poor seeing, on January 8, 1994, and could not see the trio of stars.  My second attempt to see the trio of stars was in January, 2020, but again with poor seeing and transparency, and was unable to see any of the faint stars.   

Pencil sketch, with the colors inverted:   

 

image001

 

 

We welcome our newest participant, Uwe Glahn of Germany:  

Uwe Glahn is an accomplished German observer whose sketches are a joy to behold. They appear in many publications, including my own articles. In the Interstellarum Deep Sky Guide alone, there 821 sketches penciled by Uwe and co-author Ronald Stoyan. You can view Uwe’s remarkable sketches on his website http://www.deepsky-visuell.de/ and learn more about his technique, telescopes, and achievements by putting that URL in Google translate https://translate.google.com/   –  Sue French

 

Uwe Glahn: Observer from Germany

Telescope: 27-inch f/4.2 Newtonian @ 293×.

Seeing: IV, NELM 7.0+

NGC 1931 and Parsamian 1 (a cometary nebula in southern part of NGC 1931)

 

http://www.deepsky-visuell.de/Zeichnungen/NGC1931.htm

 

NGC1931

 

 

Gus Johnson: Observer from Maryland

Could not see NGC 1931 on a clear night with a 5-inch at 24×. I also attempted with an H-beta filter at 30× and a UHC filter, however to no avail.  On another night in February 1985, I saw it with an 8-inch reflector @ 40×. Small, fairly bright mostly round nebulosity. Could not see the small trapezium of stars.

 

Joseph Rothchild:  Observer from Massachusetts

I observed NGC 1931 in Auriga on February 21, 2020.  I observed with my 10-inch reflector under dark skies on Cape Cod.  It was best seen with a 14mm eyepiece at 88×. 

The cluster was found near Phi Aurigae, between M36 and M38. I saw a loose collection of approximately 10 stars (probably background stars) with one brighter star surrounded by a small area of nebulosity. I did not see multiple stars in the cluster itself, but in retrospect may not have used high enough magnification.  Overall, it was much less impressive than its nearby Messier clusters in Auriga, but still interesting to see for the first time.

 

James Dire:  Observer from Illinois 

NGC 1931 is a mixed emission and reflection nebula with an embedded star cluster found in the constellation Auriga. The nebula is an active star forming region. The complex is located about one degree west and a tad north of the star cluster M36. NGC 1931 also lies 5.75 degrees north and one degree east of the star Elnath. NGC 1931 measures roughly 3 arcminutes in size and lies 10,000 light years away. The nebula is estimated to be magnitude 10.

NGC 1931 contains myriad young, hot O and B stars whose radiation is responsible for the blue hues of the reflection nebula. Four stars in the center of the nebula form a trapezium similar to that in the Orion Nebula. Sometimes NGC 1931 is considered a mini version of the Orion Nebula. A much larger vast region of nebulosity known as IC 417 surrounds NGC 1931. The emissions from IC 417 are the characteristic red colors from H II ions.

My image of NGC 1931 was taken with an 8-inch Ritchey–Chrétien telescope operating at f/6.4 with the use of a focal reducer/field flattener. The camera used was an SBIG ST-2000XCM CCD cooled to -20°C. The exposure was 100 minutes. The bright white area in the center contains the trapezium. The exposure was not long enough to bright out the red emissions of IC 417, which would have filled most of the region captured in this image.

NGC1931

 

Mike McCabe:  Observer from Massachusetts  

It’s been a while since I’ve participated in the observer’s challenge as I’ve been busy with other projects, so it felt good this past Saturday to prepare my charts and do a little research on the object at hand. 

I conducted this observation from Nike Field which is located in Rehoboth, MA. The conditions were pretty good for these parts – maybe a Bortle 5 sky with transparency starting at 3/5 and dropping off to 2/5, and the seeing fluctuated between 2/5 and 3/5 throughout the evening. 

I made my observation using a 10-inch f/5 Newtonian reflector. NGC 1931 is a tiny emission and reflection nebula that is said to be a miniature version of the Orion Nebula, replete with a trapezium of stars and all. 

The target was easy enough to find and showed up right away as a small fuzzy at medium powers, but all my research suggested cranking it up, so I bumped up the magnification to 250× and set down to make my sketch. If there is indeed a trapezium at the center of the nebulosity it was lost on me – the best I could do was what appeared to be three stars, and the nebulosity was there with direct vision but bloomed up nicely with averted vision. The brightest star of the bunch in the .25º TFOV was about magnitude 11 with all others coming in dimmer than that. The size of the object itself spanned no more than about 4′ on the sky, so really quite small.

fullsizeoutput_123b

 

Viadislav Mich:  Observer from Massachusetts

Date: Jan 20, 2020

Location: White Mountains National forest, New Hampshire

Conditions: Bortle 2, average seeing

Using: 22-inch f/3.3 DOB with a 21mm eyepiece (~88×, FOV~65′), 10mm (~185×, FOV~33′), NV intensifier (~92×, FOV~26′)

Filter:  5nm Ha filter used with NV intensifier

Notes: Stars in the open cluster seems to be forming line and arch patterns (or is it my brain forming them?).  Only the core of the nebula could be seen in 21mm and 10mm eyepieces. It looks like elliptical galaxy. When switching to NV intensifier with 5nm Ha filter, I was able to see extended nebulosity around the core, forming U-shaped halo.

image001

 

Glenn Chaple:  Observer from Massachusetts 

Sketch:  NGC 1931, as seen with 4.5-inch f/8 reflector at 150×. Field diameter is 0.4 degrees.

fullsizeoutput_123c

On an evening with a magnitude limit of 5 and so-so seeing conditions, I viewed NGC 1931 by star-hopping from 5th magnitude phi (φ) Aurigae. With my 4.5-inch f/8 reflector and a magnifying power of 150×, I could make out what appeared to be a 10th magnitude nebulous “star.” A switch to a 10-inch f/5 scope and 208× brightened the nebula and split the star 

(HJ 367), magnitudes 11 and 12, separation 8 arc-seconds), but atmospheric turbulence prevented me from seeing any other embedded stars.  Glenn  

 

Corey Mooney:  Observer from Massachusetts

I live stacked NGC 1931 with my EAA rig on January 29th. I set up at a nearby athletic field in Sudbury MA for better horizons. Once setup, my system could be operated remotely, so I placed my control tablet on the folded-down passenger seat of my car and I was able to comfortably sit, view and control from the back seat while being shielded from most of the elements (still bundled up for the cold). 

When I slewed to NGC 1931 using short, 2-second exposures, I was able to detect a little bit of nebulosity around the central stars. I zoomed into the live view to look at the stars. I decreased the rolling exposure to 1s, 0.5s then to 0.25s to try and split the SW “trapezium” star. But no luck. It was definitely elongated, but no separation. Maybe a bigger image scale would do it.

After examining the central stars I set the exposure to 8s and began live stacking. As it stacked the red/pink emission nebulosity surrounding the central stars became much more visible. After playing with the histogram stretch the structure of the surrounding gas and dust started to show up. There were darker, opaque areas just to the north and SE of the cluster and there was a faintly rim-lit area farther out to the SW. The faint blue reflection nebula around the mag 11.1 star 3.5′ south of the cluster was also visible; it was much fainter than the emission nebula around the cluster. 

fullsizeoutput_123d

 

Chris Elledge:  Observer from Massachusetts

On January 26th @ 7:28pm EST, I used a 10-inch f/5 refractor to observe NGC 1931 from the ATMoB Clubhouse. Sky conditions were: Bortle Scale 6; NELM 5.0; Transparency: Fair; Seeing: Average.

With Auriga approaching zenith, I was able to detect the approximate location of Phi Aurigae and its associated cluster with naked-eye averted vision. Centering this area in a 35mm 1.9º FoV, the NGC 1931 cluster was visible at the Eastern edge of the view.

At 115× (11mm 0.71º FoV) there is a group of mag. 11 stars forming a square with corners in the NE, SE, SW, & NW directions (TYC 2411-1002-1, TYC 2411-2115-1, TYC 2411-2320-1, & BD+34 1074A). The NW star of the square has visible nebulosity around it. A close pair of mag. 11 stars (TYC 2411-2086-2 & TYC 2411-0996-1) are located to the East of the SE star of the square. Two more mag. 11 stars sit to the West of the square. One West of the SW corner (TYC 2411-2209-1), and one West of the NW corner (TYC 2411-2224-1).

At 270× (4.7mm 0.3º FoV) the NW star (BD +34 1074A) of the square has a small concentration of nebulosity around it. It makes a cone from the East side of the star and spreads out a short distance arcing between the North and West. Three stars of the tight trapezium cluster containing BD +34 1074 A and B are easily split and visible. A 4th star, mag. 14, was sporadically visible when the seeing settled.

 

Michael Brown:  Observer from Massachusetts 

I observed NGC 1931 in my 8-inch SCT and 9mm eyepiece, on January 29 and February 23, 2020. The object appeared to me as a small, sparse, open cluster with a surrounding area of nebulosity, with the brightest part of the nebula apparently south of the main cluster. In the center of the nebula is a pair of relatively bright stars, which I was able to see with direct vision (as opposed to averted vision) after studying the object for a few minutes. With averted vision, I was able to see a third star northwest of the pair.

While not the “object of the month,” I decided to check out nearby NGC 1893. This is also a cluster and nebula, but much brighter, with an elongated, curved shape.

 

Richard Nugent:  Observer from Massachusetts

The nebula is visible through the 10-inch as a small, faint, amorphous glow surrounding a small, nearly equilateral triangle with stars of 11th, 12th, and 13th magnitude. On 28 February 2020, skies were very stable with the 5th and 6th stars of M42’s Trapezium visible through the 10-inch scope at 250×. NGC 1931 showed the nebulosity even at 50×; however, the 13th magnitude star of the triangle was only visible at 250× with averted vision.

Earlier in the month, the 20-inch telescope showed the three stars easily, with two 14th magnitude stars straddling the triangle and a slight hint of a nearby 15th magnitude star.

With Steve Clougherty’s 18-inch telescope, the 15th magnitude star was visible with averted vision. Through the club’s 25-inch scope, that star could be viewed with direct vision. The skies in Westford have about a 0.5-magnitude advantage over those in Framingham.

NGC 1931 With Magnitudes - Mar 5 2020 - 10-34 AM

 

 

 

 

 

 

NGC 1999 – Reflection Nebula With Hole: January 2020 – Observer’s Challenge Report

January 23, 2020

rogerivester

MONTHLY OBSERVER’S CHALLENGE

Compiled by:

Roger Ivester, North Carolina

&

Sue French, New York

January 2020

Report #132

NGC 1999 Reflection Nebula in Orion

Sharing Observations and Bringing Amateur Astronomers Together

Introduction

The purpose of the Observer’s Challenge is to encourage the pursuit of visual observing. It’s open to everyone who’s interested, and if you’re able to contribute notes, and/or drawings, we’ll be happy to include them in our monthly summary. Visual astronomy depends on what’s seen through the eyepiece. Not only does it satisfy an innate curiosity, but it allows the visual observer to discover the beauty and the wonderment of the night sky. Before photography, all observations depended on what astronomers saw in the eyepiece, and how they recorded their observations. This was done through notes and drawings, and that’s the tradition we’re stressing in the Observer’s Challenge. And for folks with an interest in astrophotography, your digital…

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NGC 1999 – Reflection Nebula With Hole: January 2020 – Observer’s Challenge Report

December 12, 2019

 

 

MONTHLY OBSERVER’S CHALLENGE

Compiled by:

Roger Ivester, North Carolina

&

Sue French, New York

January 2020

Report #132

NGC 1999 Reflection Nebula in Orion

Sharing Observations and Bringing Amateur Astronomers Together

Introduction

The purpose of the Observer’s Challenge is to encourage the pursuit of visual observing. It’s open to everyone who’s interested, and if you’re able to contribute notes, and/or drawings, we’ll be happy to include them in our monthly summary. Visual astronomy depends on what’s seen through the eyepiece. Not only does it satisfy an innate curiosity, but it allows the visual observer to discover the beauty and the wonderment of the night sky. Before photography, all observations depended on what astronomers saw in the eyepiece, and how they recorded their observations. This was done through notes and drawings, and that’s the tradition we’re stressing in the Observer’s Challenge. And for folks with an interest in astrophotography, your digital images and notes are just as welcome. The hope is that you’ll read through these reports and become inspired to take more time at the eyepiece, study each object, and look for those subtle details that you might never have noticed before.

NGC 1999 Reflection Nebula in Orion

NGC 1999 is a bright, 2′ reflection nebula embedded in the southeastern reaches of the more diffuse, 10′ reflection/emission region IC 427. Clasped near its heart, the variable star V380 Ori provides the nebula’s illumination, its visual magnitude varying from magnitude 9.5 to 11 during the past decade. A dark patch shaped somewhat like a chess pawn trends west-southwest from the star. It was long thought to be a type of dark nebula known as a Bok globule, but recent studies show that this inky spot is most likely a dark cavity within the reflection nebula.

Sir William Herschel discovered NGC 1999 on October 5, 1785.His journal entry from that date reads: “A star with a very strong burr all around.”

 

January:  NGC 1999 – Refection Nebula with hole – Orion; Mag. V=9.5;  Size 2′ 

RA:  05h  36m   Dec.  -06º  43′  

Finalized Observer’s Challenge Report:  JANUARY 2020 OBSERVERS CHALLENGE _ NGC 1999

Reports to-date:  “Work File” for organization of final report:  

 

Mario Motta:  Observer from Massachusetts 

Processed NGC 1999 (Keyhole Nebula) which is the January Observer’s Challenge object.   I did not realize how much dust and gas surrounding area, when imaged. 

This is a total of 166 minutes of H alpha, Sulfur, and O3 filters.  Not much O3 in the final.  Mostly hydrogen with some sulfur.

I’ve sent a B&W composite, and also color.  All taken with my 32-inch f/6 telescope, with STL 1001E SBIG camera. 15×15 arc minute view for scale, the actual keyhole is small, but very bright, the surrounding dust/gas is faint

Processed in PixInsight.    Mario Motta 

NGC1999

NGC1999-C

 

Vladislav Mlch:  Observer from Massachusetts

January 2020 Observer’s Challenge report:

Object: NGC 1999

Date: Dec 28, 2019

Location: White Mountains National forest, New Hampshire

Conditions: Bortle 2, average seeing

Telescope:  22-inch f/3.3 DOB with 21mm eyepiece  (~88x, FOV~65 arcminutes, and a 6mm (~300x, FOV~18 arcminutes)

Filter:  No filter used

Notes: Nebula looks like a “blue snowball” in the 21mm eyepiece and it looks like a “big snowball” in 6mm eyepiece. At 300x one can see dark nebula in the middle of the snowball, shaped like Texas. There is a bright core next to the dark nebula.

Pencil sketch below:

ngc1999

 

Roger Ivester:  Observer from North Carolina 

Reflection nebula, NGC 1999 is easy to locate and see at all magnifications, with a 10-inch reflector.  The nebula has a fairly high surface brightness.   

At a magnification of 104x, the reflection nebula appears as a bright circular haze, with a much brighter concentrated center.  When increasing the magnification to 256x, the illumination star V380 which is variable (mag. 9.5 to 11.0) can be easily seen, appearing a little east of the center.  

The offset of this star brightens the eastern section of the nebulous halo, causing the appearance of greater concentration and being brighter.  

After spending two hours, I could not see the dark void or hole just to the west of the variable illumination star.  However, I believe with better seeing this “noted” feature would have been possible, using the 256x magnification, but on this night, stars were very soft and bloated.   Pencil sketch as following:

NGC 1999 Roger

 

Joseph  Rothchild:  Observer from Massachusetts  

I observed NGC 1999 on January 15, 2019 on Cape Cod.  I again used my 10-inch  reflector under dark but hazy skies. 

The object was easily found by star hopping from Iota Orionis.  There was an asterism appearing like a reverse 3 or a question mark that pointed to the nebula. 

When using a low magnification of 45x, it appeared like a fuzzy star.  At higher power of 153x, there was a compact nebulosity around a star, seen best with averted vision, while with direct vision it appeared almost stellar.  With averted vision I was able to see the hole with difficulty just adjacent to the central star.     

 

James R. Dire:  Observer from Illinois 

NGC 1999 is a bright reflection nebula containing a very dark nebula, all part of a vast region of molecular clouds located in Orion. NGC 1999 can be found by following Orion’s Sword south one and one-third degrees past the Trapezium. The brightest part of NGC 1999 glows colorless or white over a region 16 x 12 arcminutes in size. Embedded within this region is a dense dark area, triangular shaped, a few arcminutes on each side.

Finding NGC 1999 in January 2020 from Peoria, Illinois proved difficult due to the weather. The month only offered up one clear night with no interfering moon. On that night, I ventured out to my observatory 20 miles northwest of downtown Peoria, located in a state park. I arrived at sunset. The temperature was 18°F and there was several inches of snow that fell two nights earlier, followed by freezing rain making everything icy and crusty.

I cleared the snow off of my Sky Shed Pod and opened the roof. https://rogerivester.com/2019/08/19/skyshed-pod-personal-observatory-by-guest-host-james-dire/

Orion was still fairly low in the southwest, so I spent a couple of hours imaging the NGC 708 galaxy cluster http://astrojim.net/Galaxies/NGC708.html before turning my attention to NGC 1999.

The seeing was terrible, around 4 arcseconds, but the transparency was quite good. I imaged NGC 1999 using an 8-inch f/6.4 Ritchey–Chrétien reflector with a SBIG ST-2000XCM CCD camera. 

I combined nine 10-mininute exposures to create the accompanying image of NGC 1999. During he exposure, Orion was embedded in the light pollution over Peoria. I normally only photograph objects to the north or west where the light pollution is minimal. But the only way to capture this image was towards the city, were the sky glow is at its worst. This along with the poor seeing made for an image that left a lot to be desired.

Our observatory complex does not have a warm room. So I put a space heater plugged into shore power under the hatch in the back of my Subaru and folded down one back seat to use as a desk while I sat in the other back seat. With my laptop in the car plugged into a power strip along with a Wi-Fi router, I connected remotely to the computer in the dome to control the telescope and camera. The space heater kept the temperature in the car warm enough so I could remove my hat and gloves and unzip my winter coat. By the time I left at 11:15 p.m., the outside temperature was 14° F. As you might guess, it was much too cold outside to set up a telescope and view NGC 1999 through an eyepiece. But I believe my image captured similar detail that I would have seen in my 14-inch, f/6 Dobsonian.

NGC1999

 

John Bishop:  Observer from Massachusetts 

On January 22, 2020 I observed reflection nebula NGC 1999 from the ATMoB Clubhouse in Westford, MA. The sky was clear, with transparency and seeing being only fair. The temperature was around 30ºF at sunset, but dropping to 18º by 9:30 pm.

I observed with my 8.25-inch f/11.5 reflector (210/2415) at 48×, 130×, and 193×. I did not use any filters.

This is a rich area of the sky. Showcase object, M42 is close by, as are two pretty clusters, NGC 1981 and NGC 1980. NGC 1999 did not require much star hopping to locate. Using my 2-inch barrel, 50mm eyepiece at 48×, I briefly swept the field just south of NGC 1980. 

Almost immediately, I noticed a small patch of nebulosity surrounding a star-like object. It looked different than the nearby field stars. This was NGC 1999, but initially I was not quite sure what it was – nebula? cluster?  At low power, the bright core and nebulosity even gave it the appearance of a very distant or compact galaxy.

Higher magnification produced a larger, brighter image. At 193×, the nebula was more or less round. The bright core, which did not resolve, was slightly elongated and a little flattened on one side. I believe this was the “keyhole” silhouetting the bright core, although I could not see the keyhole itself.

One twist on this evening’s session was that I had to observe without the benefit of the motor drive on my equatorial mount. The connecting plug to my power source broke during setup, there was no spare. Usually I can lock onto an object and observe it at my leisure. I missed that luxury, as NGC 1999 flew by in the field of view, especially at 193×. 

I tip my hat to my Dobsonian colleagues who always track by hand.  The observing session ended early due to clouds rolling in. I would like to observe this object again to try to see the keyhole. I would also like to try observing this object with filters.  

 

Corey Mooney:  Observer from Massachusetts 

On December 20th I live-stacked NGC 1999 from the clubhouse in Westford, MA. I was using an 8-inch f/4 Newtonian with a coma corrector, and an ASI294MC-Pro camera. 

NGC 1999 was just barely visible in the 4-second framing exposures, when I switched to 8 seconds and started live stacking it really came to life. The crisp keyhole shape punched out of the soft reflection nebula was sharply defined. 

NCG 1999 is imbedded in the same complex of gas and dust as the Orion nebula. This thick and soupy home results in some very intriguing surroundings. As the short 8-second frames continued to add to the stack, other objects started to appear out of the murky darkness. 

Immediately south of NGC 1999 there are the two red glowing gashes of Herbig-Haro object 1 & 2. These are jets of ionized gas ejected by a newborn star! To the north of NGC 1999 is the extremely faint diffuse blue glow of IC 427, farther north beyond that is the brighter golden glow of IC 428.

fullsizeoutput_1237

 

Venu Venugopal:  Observer from Massachusetts 

I finally got my first scope, very first camera, and mount.  It was my decision to hold off from buying any devices for a year, since the time I first decided to take up astronomy as a hobby.  My first light was on January 17, 2020, with below freezing, New England temperatures, with a clear night at the clubhouse. 

Tools used:  IOptron GEM45, 8-inch f/4 Newtonian with a comma corrector, ZWO ASI 533 cooled color (gain at 80%, 8-15 seconds exposures for about 30 minutes).  I let sharpcap do the work, and used a bahtinov mask for focusing.  No darks, flats or bias.  I was glad to have been successful in getting NGC 1999 on the first try.  I think the colors did not stretch correctly.  (Thanks to Corey Mooney for helping me with the astrophotography set up).

image3

 

Richard Nugent:  Observer from Massachusetts 

Observing from my Framingham location the NELM is typically around magnitude 4.8 however, snow cover reduces it to around magnitude 4.4.  With my 10-inch, f/4.7 Dobsonian I could easily see the star V380 Orionis, but could not detect any hint of the accompanying nebulosity. 

I tried varying the magnification, but to no avail. Nor did the use of filters (80a, UHC, and OIII) help.

Under similar conditions I observed the object with my 20-inch Dobsonian. With this telescope the nebulosity was visible at all magnifications. It appeared as a faint, diffuse, uniform glow with no definite border. I could not detect the hole in the nebula.

I would suggest that NGC 1999 requires a dark sky location to be fullyappreciated.

 

Gus Johnson:  Observer from Maryland 

February 1985:  8-inch reflector @ magnification of 75x, appearing as a faint mostly round nebula with center star.  Also could see using 40x and a UHC filter.    

February 1986:  4.25-inch reflector, easily located and visible, despite a five day moon.  Very easy with 8-inch reflector.  

 

Chris Elledge:  Observer from Massachusetts 

On January 26th @ 8:07pm EST, I used a 10-inch f/5 refractor to observe NGC 1999 from the ATMoB Clubhouse. Sky conditions were: Bortle Scale 6; NELM 4.5; Transparency: Fair; Seeing: Average.

I attempted to observe NGC 1999 while battling with partly cloudy skies that repeatedly obscured Orion. I was able to observe it several times at low power, but I was never able to switch to high power before more clouds moved in. 

NGC 1999 is easy to locate since the southern edge of M42 and Nair al Saif fit in the 1.9°FoV of my 35mm eyepiece. Placing Nair al Saif on the NNW edge of the view and d Orionis on the SE edge drops NGC 1999 right in the middle.

At 36× (35mm 1.9˚FoV) there is a line of 3 magnitude 8 to 9 stars stretching 44 arcminutes from the SW to the NE (HD 36813, HD 37001, and HD 37131). There are two magnitude 10 stars perpendicular to this line about 20 arcminutes SE of HD 37001. The two stars are TYC 4778-1138-1 and V380 Orionis. V380 is the further of the two stars to the SE and has visible nebulosity surrounding. That’s the bright core of NGC 1999.

At 115× (11mm 0.71°FoV) the nebulosity of NGC 1999 around V380 Orionis is visible with direct vision. The nebulosity quickly fades just a short distance from the star. The center of the glow seems to be slightly offset towards the SW direction from the star. I am unable to see the keyhole feature at this magnification.

 

 

 

 

 

    

 

IC 1805 – “Cluster + Nebula” In Cassiopeia – December 2019 – Observer’s Challenge Report #131

November 23, 2019

 

MONTHLY OBSERVER’S CHALLENGE

DECEMBER 2019

Report #131

IC 1805 Open Cluster in Cassiopeia

Observer’s Challenge Report Final:  Click on the following link

DECEMBER 2019 OBSERVERS CHALLENGE – IC-1805

 

Note:  The following are mostly original notes, with very little if any editing, to preserve the feelings and thoughts of the observer during the observation.  This is not the “official” Observer’s Challenge report, but what I call a “work-file” just to organize the entries.  Roger Ivester

     IC 1805 is a 6.5-magnitude cluster about 62 stars that spans about 20 arcminutes. It’s nearly centered on the group’s brightest member, HIP 11832 shining at magnitude 7.1. The cluster is young at only 2.5-million years and we see it at a distance of roughly 6,500 light-years. IC 1805 is enveloped in and associated with the emission nebula Sharpless 2-190, commonly called the Heart Nebula, which sprawls across 1.6 º of sky.

     Edward Emerson Barnard discovered IC 1805 photographically and included it on the first two plates of his wonderful Photographic Atlas of Selected Regions of the Milky Way.  The atlas can be viewed online at:

https://exhibit-archive.library.gatech.edu/barnard/     Intro by Sue French  

 

IC 1805, December 2019, Observing Report by Mario Motta:

B&W image of IC 1805:  An H alpha image taken through my 6-inch refactor in 2015 for wide field. And has 7,  20 min subs, so 2 hours 20 min of H alpha.  

Color Image:  This was combined with 1 hour each of Oxygen 2 filter and Sulfur filter:  See attached.

IC 1805 (the Heart Nebula), North is to the right on this image, rotated to show the “heart” shape more readily.

Of course…to a cardiologist the Right heart (on the left, person facing you), is very “enlarged” so this is a rather sick heart, with what I would call right heart failure.    Mario Motta 

 

IC1805-heart

IC1805

 

Sue French: Observer from New York:

14×70 binoculars:

IC 1805 is a fairly large, loose open cluster of six to eight moderately bright stars, depending on the borders, plus about 15 more stars on the backdrop.

105/610mm (4.1-inch f/5.8) refractor

     17×: Nebulosity is faintly visible without a filter, a little better with a UHC filter, and very nice with an O III filter. The brightest areas include: the IC 1805 cluster; a wide arc that runs between clusters IC 1805 and NGC 1027 and then loops around north of the IC 1805 cluster; and a small patch in the position of the nebula complex NGC 896/IC 1795. A fainter arc starts between the two clusters, loops around south of cluster IC 1805 and then northward on the western side of this cluster.  Both loops are quite patchy with very uneven brightness. Nebulosity also stretches from cluster IC 1805 to the eastern loop.

     87×: About 40 stars are visible in cluster IC 1805. Its brightest member is a double star, residing in a rough circlet of fainter suns at the cluster’s heart. Arms of stars starting north and south of the circlet curve westward. Two fairly bright stars northeast form a faint star with the lucida.  A broad scattering of stars straggle east through southeast from the circlet, while extremely faint specks of light can be seen within the circlet and rounding out the group.

     The double star is Stein 368 AB (STI 368 AB), PA 97º, separation 9.9″, component magnitudes 8.0 and 10.1. NGC 1027 displays about 50 stars centered on the group’s central lucida. Starting north-northwest of the star, its brightest attendants spiral outward from it for about 1½ turns.

     These observations were made in the northern Adirondack Mountains of New York, where my naked-eye limiting magnitude near Polaris was 6.3.

 

Roger Ivester:  Observer From North Carolina 

     In November I used a 6-inch f/6 reflector in an attempt to see the nebula in IC 1805. My eyepiece of choice for this night was a 2-inch-barrel 26mm with an O III filter. This gave me a field of view of 2º. 

     Scanning the area before using the O III filter, I first saw open cluster NGC 1027. A bright cluster at magnitude 6.7, consisting of about 20 stars with one brighter member located in the center. This cluster is located just to the east of IC 1805. 

     Now to IC 1805: I could easily see the cluster of stars located in the central region of the IC 1805 nebula. When adding an O III filter, I scanned the area for more than an hour; however, I cannot say definitively that I could see any nebulosity.

     On December 15, 2019, I used an 80mm f/5 refractor, with a 24mm eyepiece and a UHC filter. I was a bit dubious before beginning my observation that I’d be able to see the IC 1805 nebula based on my results using a 6-inch reflector only a month earlier, and with similar sky conditions. 

     After about thirty minutes, I could not see any of the nebula, but the central stars were easy and bright. However, when I began using my “manual” slow-motion controls, I began scanning across the IC 1805 area, and to my surprise, I began seeing very faint brightenings in the area. I scanned one section at a time, and was able to sketch extremely faint tentacles and fingers of nebulosity, only marginally brighter than the background. After more than two hours of “slow-motion” scans, well over two hundred crossings, I was able to sketch some of the brighter sections, encircling the central cluster. 

 

Roger IC 1805

Telescope: 80mm f/5 achromatic refractor 

Eyepiece: 24mm + UHC filter 

Sketch Magnification: 17× 

Field of View: ~3.5º 

 

James Dire:  Observer From Illinois 

     The Heart Nebula, IC 1805, is part of a vast complex of nebulae located in the constellation Cassiopeia. The nebula is located five degrees southeast of the star Segin and eight degrees east of the star Ruchbah. Segin and Ruchbah are the two easternmost stars making up Cassiopeia’s “W” asterism. 

     The brightest part of the Heart Nebula is separately known as NGC 896. NGC 896 was discovered by William Herschel in 1787 using his 18.7-inch reflector. NGC 896 measures 27 x 13 arcminutes and is estimated to be magnitude 10.

     The Heart Nebula itself extends about one degree in both right ascension and declination. The Heart Nebula lies 7500 light years away in the Perseus arm of the Milky Way Galaxy.

     IC 1805 is also the designation of an open star cluster in the middle of the Heart Nebula. This cluster is also known as Melotte 15. This loose open cluster is estimated to be a mere 1.5 million years old and contains several bright stars 50 times the Sun’s mass. These stars are responsible for exciting the hydrogen gas in the Heart Nebula resulting in the red glow as seen in photographs.

     My image of IC 1805 was taken with a 71 mm f/4.9 apochromatic refractor using an SBIG STF-8300C CCD Camera. The exposure was 140 minutes. In the image north is up and east to the left.

     The second image has labels pointing out the location of NGC 896 and the central star cluster in IC 1805. Two more open clusters are labeled in the image. The first is NGC 1027 located on the east side of the heart. NGC 1027 is a bright rich cluster of approximately 50 stars all within a 20 arcminute circle. The cluster has a total magnitude of 6.7. The other cluster is called Markarian 6 and is located southwest of the heart. Markarian 6 is magnitude 7.1 and is 6 arcminutes in diameter. All three star clusters contained in the nebula are worthy of inspection with any telescope at medium to high powers.

     My best view of the Heart Nebula was with my 14-inch f/6 Dob using a 26mm eyepiece (82x). This combination provides a one-degree true field of view. While the view comes nowhere close to my image, it was possible to see many of the brighter regions of the nebula, especially NGC 896 and the three above-mentioned star clusters.    

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Michael Brown:  Observer from Massachusetts

     I was not certain I would do any observing this month, as we have been having a lot of cloudy nights, and it has been an unusually cold December. I have become reluctant to brave the cold in recent years.  

     Tonight (12/20/19) was so clear, with no moon, and at least not quite as frigid as earlier this week, that I decided to venture out.  Nevertheless, by the time I came inside, the temperature had dropped to 17 degrees F.  

     IC 1805 is an open cluster surrounded by a large nebula.  I observed it with my 8-inch SCT and a 25 mm eyepiece (my largest/lowest power), which has a field somewhat less than 1º field of view.    

     The cluster is fairly sparse, with six bright stars and perhaps a couple dozen dimmer stars visible.  Near the center is an oval-shaped group of stars.  About 1 degree southwest of the cluster is an interesting asterism of five stars shaped like a backwards “J”.  

     A hint of nebulosity was apparent within and surrounding the cluster.  This was more obvious after used a UHC filter on the eyepiece.  

     Because the nebula is considerably larger than my field of view, I slewed in all directions from the cluster to explore it.  In general, the nebulosity appeared to extend a couple of degrees in each direction, before the sky background became fairly dark, indicating I was no longer within the nebula.  

     About 1 degree east of the cluster, I saw a bright star and the brightest knot of nebulosity.  To the north of the cluster the nebulosity also appeared bright and mottled in some areas.  In the northern area, I possibly saw a narrow filament of brighter gas, oriented east-west.

     I can see why a wide-field telescope (which I unfortunately do not have) would be a good instrument for this object.    

 

Chris Elledge:  Observer from Massachusetts

     On November 30th @6:52pm ESTA, I used a 102 mm f/7 refractor to observe IC 1805 from the ATMoB Clubhouse. Sky conditions were: Bortle Scale 6; NELM 5.0; Transparency: Above Average; Seeing: Poor.

     I found IC 1805 in the Dobsonians that tried by star hopping from Segin and heading SE via triangle of mag. 8 stars (HD 12623, HD 12819, and HD 12568) and a zigzag group of mag. 7 and 8 stars containing HD 13686. Several bright mag. 6 and 7 stars surround IC 1805, and the center cluster of it is quite bright so it’s easy to tell when you’ve found it. The refactor I used for this observation was on a goto mount, so it felt a bit like cheating compared to my usual reflector observations.

     At 20x (35 mm, 3.4˚FoV) The central cluster of IC 1805 is composed of 10 bright mag. 7 to 8 stars. There are two parallel North/South lines of 4 stars. There is a scattering of mag. 8 and 9 stars all around the outer edges of the nebula. There is a faint glow all throughout the center of the view, but the ESE and NNE sides are notably darker. Moving the view around makes it clear that the IC1805 area is brighter than the surrounding areas. The extents of the nebulosity seem to end near a line of mag. 9 to 10 stars on the North side. It continues on the WNW side towards another cluster of stars that is in NGC896. There is a faint rift between the nebulas in a NE to SW direction. The nebulosity’s Southern bounds is at a WNW to ESE line of mag. 8 and 9 stars on the South side. A tiny cluster Markarian 6 sits right on the SW edge of the nebulosity. The brightest nebulosity is concentrated around the central cluster of stars.

     Adding a UHC filter reveals some mottling in the nebulosity outside of the the bright center nebulosity around the cluster. The ESE edge of the nebula appears brighter than the inner portions. A faint finger of glow stretches to the NE from the Eastern edge of the nebula. Replacing the UHC with a Hydrogen-Beta filter darkened the stars and the brightest central nebulosity, but the edges of the nebula stand out more with some visible mottling inside the two lobes of the heart shape.

     Below are the observing hints that I wrote up for others attempting this based on observing through several telescopes:

     I spent the night of November 30th observing IC 1805 through a variety of telescopes with various filters at the ATMoB Clubhouse. The best view that I got was through a 102 mm f/7 refractor with a 35mm eyepiece providing a 20x mag and 3.4˚ FoV. I recommend using a UHC to see the most nebulosity. While the edges of the nebula were still difficult to determine exactly where they stopped, it was clear that areas around the nebula were darker than the area inside.

     I actually found a Hydrogen Beta filter to be useful on this object. In my refractor with an H-beta filter (on the wide side for bandwidth) I was able to observe that the outer edge of the nebula was slightly brighter than parts of the middle. Some mottling was visible within the nebula outside of the brighter star clusters. This filter makes everything else really faint.

     I was able to observe the nebulosity in both my 10-inch f/5 Dob (36x, 1.9˚) and the ATMoB 25-inch f/3.5 Dob (63x, 1.1˚). In both cases it required extensive panning of the view to determine that the field was brighter within the nebula than outside. It was difficult in both cases to determine where exactly the edge of the nebula was. Sitting the view on the edges of the nebula, I could tell that one side of the view was brighter than the other. Filters helped, but the view through the 20x power of the 102 mm refractor was better.

Conclusions:

     Low magnification definitely is important to this one. Probably works best with the biggest aperture you can find that still gives 20x or lower magnification at a reasonable exit pupil. I don’t think anything over 5-inches  will improve visibility. Don’t bother with OIII unless you want to just see the nebulosity around the bright clusters. UHC is ideal. H-beta is fun if you happen to have one that fits your lowest power eyepieces already.

 

Sameer Bharadwaj:  Observer from Massachusetts  

William Optics GT71 w/ 0.8x flattener

Optolong L-enhance filter, Canon EOS 77D modified

12 x 360 seconds, Ioptron zeq25 guided with QHY5L2M

     Pursued the Heart Nebula all summer with an unmodified camera with limited success. This is the object that finally motivated me to get the camera modified.    Sameer Bharadwaf

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Ed Fraini: Observer from Texas

     My observation of IC 1805 and its neighborhood took place on the evening of December 22 at the North Houston Astronomy Clubs dark site near Dobbin, TX.  We had just that one night of clear cold sky following the passage of a cold front.  The sky conditions were recorded at the end of the observing session and are reported as follows;  The overhead sky measured 17.45 SQM, Transparency above average with three stars magnitudes 6.1 to 6.3  in Cassiopeia visible with direct vision, and  Seeing was excellent from sunset throughout our observation.  Both Vega and Capella were bright and steady at sunset, and they were used as the Sky Commander alignment stars for the 20-inch dob.

     The observing plan was to locate IC 1805 as quickly as possible after sunset, which was at 2330 GMT.  Then to determine how soon nebulosity could be detected as the sky darkened. 

 Time 0010 GMT: 

     Not yet astronomical dark, with strong twilight to the west.  Cassiopeia is high towards the north.  40 mm eyepiece giving a very low 48x.  IC 1805 stands out well, counted 17 stars of which most appeared to be close in magnitude and color.  Only three stars exhibit a slight yellow hue.  The cluster is well separated from other field stars making it easy to identify.  This cluster would be classed as widely dispersed in my judgment. It seems lines would be the characterization of the organization of the stars in the group, and many lines are moving across the field from the central area. Already we can see nebulosity, very light but there, to the north and east out towards NGC 1027.  I was very surprised that the nebulosity was so detectable this soon after sunset.

Time 0020 GMT:  

      I moved IC 1805 off to the northeast out of the field of view until Mrk6 appeared in the 40mm eyepiece.  Mrk6 is a beautiful small asterism that I will refer to my fellow observers as “The Worm.” A quick look at 142x revealed no color and equal magnitudes for this collection of stars.

Time: 0025 GMT: 

     Now moving back to IC 1805 with the 40 mm eyepiece, the cluster is now much more distinctive, and the nebulosity very evident.  I can now count 30 to 35 stars in the field, and it still seems very dispersed.  A broader range of colors was observed at this time.

Time 0032 GMT: 

     Even though the nebulosity to the east is strong.  I installed the OIII filter, which significantly enhances the appearance of the nebulosity for the whole field. The sky background is growing darker, and there are three bright areas of the nebula that can be noted.  These are mainly on a north-west to a south-east line from NGC 896, which is bright through IC 1805 and on to the west to another bright nebula area near NGC 1027.  We can follow the opacity from NGC 1027 to IC 1805 very quickly now.  While there are several bright areas, we could not get a sense of the “heart” shape while looking at these relatively small fields of view.  Quite a bit of time trying to sort out the larger pattern of the Heart Nebula.

Time 0100 GMT: 

     Looking at IC 1805 at with a 26 mm eyepiece (without the OIII filter) gives us an exit pupil of 6.7 mm, which is a good match for my dark-adapted eye. Concentrating on IC1805, we can now count 65 – 70 stars, many of which are very dim.  The nebulosity band is substantial to the north and thins out over the cluster.  I worked my way stepwise up to 320x, in a failed attempt to see the companion to HD 15558.  An interesting note, HD 15558, is listed by Wikipedia as being one of the most massive stars in the Milky Way.  I Identified three nearby stars at magnitude 11 that were barely visible, and the companion is reported to be much fainter.  Under increased power, the star group in the center of IC 1805 looked more rectangular in nature with an L/D of 3. HD 15558 is midway on the long side bottom.

Time 0120 GMT:

Wrapped observation of IC 1805:

     To our surprise, it was easy to detect the nebulosity of this extended object quite soon after sunset. It was also a surprise how difficult it was to keep my  orientation while trying to trace out the heart which we are so all familiar with, as shown by our astrophotography friends.

 

Richard Nugent:  Observer from Massachusetts 

      IC 1805 is a VERY challenging object from my home observing site of Framingham, MA. This site offers a NELM of about 4.9 on the very best of nights. Snow cover reduces it to around magnitude 4! The  observing site of the Amateur Telescope Makers of Boston offers a slightly darker sky with a NELM of about 5.1 or 5.2 but very dark skies are preferred for this object.

     I had an opportunity in November to attempt an observation of this object from Framingham. I was using my 20-inch Dobsonian which is equipped with an internal filter slide holding UHC and OIII filters.  This telescope achieves its richest field configuration when I use my 21 mm 100° eyepiece. This yields a magnification of 120x and a true field of view of 0.83°. 

     The cluster associated with IC 1805 is easy to locate however, with this setup I could see absolutely no trace of nebulosity. Filters did not improve the detectability of the nebula. I tried increasing magnification to darken the background to no avail. The telescope has a 90mm finder that gives 20x and a 3° true field. Considering the large size of this nebulosity, I tried viewing it with this little scope. No luck. I added UHC and OIII filters and again, no luck.

     As a test, I swung the scope to the Veil Nebula. Using the finder with the UHC filter the western portion of the Veil was easy visible. The eastern portion and the nebulosity between the east and west regions was faint but definitely visible. The aperture of this scope proved to be too small to drive light through OIII filter. The failure to detect IC 1805 leads me to believe it is extremely faint!

     In December, I brought an 8-inch f/4 scope to the ATMoB site. While the stars appeared steady, the seeing was actually quite poor. However, using an UHC filter and an eyepiece that gave 50x and a true field of 1.6° I was able to see some extremely faint nebulosity surrounding the cluster. Switching to the OIII the nebulosity was brighter but still very difficult.

     Much to my dismay, I saw no trace of the arcs of nebulosity that lie about ½° to the east of the cluster.

     In my humble opinion, in order to detect this object visually, you’ll need to use an aperture/eyepiece combination that gives low magnification and a large true field of view. Once on the cluster, use UHC and/or OIII filters to enhance the nebulosity, and, as always, try to observe under the darkest skies you can find.

 

John Bishop:  Observer from Massachusetts 

     I observed IC 1805 on two nights, 11/30/19 and 12/19/19, from the ATMoB  Clubhouse in Westford, MA.  Both nights were clear and cold, dropping to 18º F. on 11/30, and 10º on 12/19. Unfortunately, transparency and contrast were only fair at best. I observed with my 8.25-inch f/11.5 reflector (210/2415) at 48x, 80x, and 100x.

     Star-hopping to a sparse open cluster in this congested area of the sky was a bit of a challenge. Cassiopeia is chock full of clusters, nebulae, and background stars. Telrad got me to the general area, but my 7×50 finder showed a field with numerous fuzzy areas and knots of stars. Which one was IC 1805?

     Using my finder and motor drive, I moved from spot to spot, and then observed at 48x. The first cluster I landed on was a sparse open cluster with a conspicuously bright central star. This proved to be NGC 1027.  I moved to another nearby object. This looked like it could be IC 1805, which it was. Out of curiosity, I turned to yet another nearby fuzzy, starlike object. This was Markarian 6, an unusual cluster of six or so stars in a curving line. Markarian 6 is so distinctive in its appearance that it was an ideal navigational mark, from which I could verify my location. (I was alerted to Markarian 6 by Luginbuhl and Skiff, later confirmed with an online image). In my finder, NGC 1027, IC 1805, and Markarian 6 formed a triangle that I could traverse with my motor drive (no Goto).

     On the advice of other observers, I used the lowest power, widest FOV eyepiece I have to observe IC 1805. This is a 2-inch 50mm eyepiece providing 48x with a 1 degree FOV. I have no filters for the 50 mm eyepiece. 48x, unfiltered, showed 10 or so brighter stars, widely spaced against a dark background, with some fainter stars about. On the first night I could see haze concentrated around several of the stars in the center of the cluster, but I could not see extended nebulosity. This was the same at 80x and 100x, unfiltered, with 1.25″ eypieces. The most I can say was that there may have been brightening of the background which could could have been nebulosity, but my FOV was too narrow to be sure. On the second night, I was prepared to try Roger Ivester’s sweeping technique, but the sky was badly washed out due to snow cover reflection, and it was too cold for extended experimentation.

     On 1.25-inch eyepieces, UHC and OIII filters at 80x and 100x were not much help. For one thing, the FOV was even narrower.  Although the stars were still visible, the images were dark, and not pleasing. I thought I saw faint differences in brightness in the area around the central stars, but the image was too dark and  faint to be useful. Bear in mind that transparency and contrast were compromised, especially on the second night.

     All in all, a good exercise in “celestial navigation”; not much success in seeing the faint, fuzzy stuff.

     Yet – an interesting thing happened as I was packing up on the second night. One of our club members was allowing fellow observers to look through his 3x  “night vision image intensifier” (NVII). When my turn came, I pointed the device at the region of Cassiopeia I had been observing with somewhat meager results. I was stunned. There, hanging in the sky off Epsilon Cassiopeia, were the two nebula associated with IC 1805 and IC 1848. They were amazingly large and bright, at 3x.

     I had never used one of these devices before.  I am still trying to sort out what this almost magical technology means for traditional observational astronomy.

 

Vladislav Mlch:  Observer from Massachusetts

Date:  Nov 30 and Dec 28, 2019

Location: White Mountains National forest, New Hampshire

Conditions: Bortle 2, below average seeing

Telescope:  22-inch f/3.3 DOB with 10 mm eyepiece (100º apparent field of view)   (185x – FOV 0.54º ) Night vision intensifier with 1.2x Barlow (92x, FOV 0.43º)

Filter:  7 nm Ha used on the NVI  

     I was able to sketch only the central portion of the cluster.  There seems to be patterns of many arches, all consisting of mostly mag. 5-6 stars.

     There was no sign of nebulosity when using a regular eyepiece. I was able to see some nebulosity with the night vision intensifier, coupled to a 7 nm Ha filter. The true field of view of the DOB was too narrow to see the entire nebula at the same time.

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Corey Mooney:  Observer from Massachusetts

     On  December 19th I had the opportunity to view the heart nebula using Vladislav Mlch’s Gen III night vision device. He had it set up for hand held use with a 3x lens (75 mm) and Ha narrow band filter.  It was like a magic eye loupe revealing the true nature of the night sky, laiden with numerous Ha regions everywhere I looked.  A truly remarkable experience!

      At the time, the heart nebula was nearly over head so I had to crane my neck to see it, but the sight was worth it.  Both the heart and the soul were clearly visible with great contrast. The heart was distinctly heart shaped with a bright outline and central band. 

     On Dec 20th  before setting up my EAA equipment at the clubhouse I tried to observe the heart visually. I used my 80mm f/7.5 ED refractor with a 50 mm 2-inch eyepiece and a UHC filter. This resulted in a wide 5° FOV at 12x with an exit pupil of 6.6 mm, which could drive a lot of light through the filter. 

      I was able to see some very faint nebulosity around the central star cluster. I also saw the fish head (IC1795) as a detached area of concentrated glow, definitely brighter than the glow around the central cluster. I did not see the fainter heart shaped outline, even after panning around and jiggling the scope with averted vision.  

     On December 28th I live stacked the heart nebula with my new IMX294 based camera in my 208 mm f/3.9 Newtonian. The new camera has a much larger sensor than my IMX224, resulting in a much larger field of view, but I was still only able to fit a choice part of the massive heart nebula into the FOV.  I chose to frame the bright central cluster of the heart and the nearby fish head nebula. 

     In the short 8s frames the red nebulosity was visible around the central cluster and the fish head, albeit very noisy. Once the live stack was started the grainy noise started to fade and I could stretch the histogram to cut the sky glow and reveal some of the fainter outline as more frames accumulated. There are wonderful wisps of nebulosity tangled in the central star cluster. The illumination/ionization from the blazing stars gives a very 3D effect to the gas and dust.

     The outline of the heart was much fainter. With aggressive stretching it could be separated from the background, but I settled on a smoother more natural look.  The fish head certainly lives up to its namesake, complete with a gill plate, lips, and an eye. It reminds me of my large pet goldfish.

     Halfway between the central cluster of IC 1805 and the brighter glow of the fish head I noticed a small open cluster of lovely golden stars magnitude 14-17. I later found out it was  called Tombaugh 4, discovered by Clyde Tombaugh while reviewing photographic plates from Lowell Observatory. 

     If I had more clear nights between the holidays I would have liked to try a wide field shot with a camera lens in order to frame the whole nebula.  I am still very happy with how the close up turned out. I look forward to getting more practice with the new camera,

IC 1805 Heart Nebula and IC 1795 Fish Head Nebula

heart and fish_Stack_bits_Gain_343frames_2744s_20_17_03_WithDisplayStretch-downresed

208 mm f/3.9 Newt, ASI294MC-Pro, SW Quattro CC,

8s x 243 = 2744s = ~46 min, live-stacked and stretched in SharpCap

NGC 246 – Planetary Nebula – Cetus November 2019, Observer’s Challenge Object

November 22, 2019

NOVEMBER 2019 OBSERVERS CHALLENGE – NGC-246